What is grid resilience?

Power outages can occur with natural disasters, cyberattacks, equipment failures and other causes. The degree to which grid operators can limit the scope, duration and impact of outages determines a power system’s level of resilience.

Grid resilience and grid reliability are closely linked terms:

• Grid reliability measures how consistently an electric grid can maintain the energy supply and meet customer needs under normal conditions.

• Grid resilience focuses on the grid’s ability to withstand, adapt to and recover from disruptions.

While the two have some overlap, a resilient grid might not be reliable and the inverse can also be true. Investments in resilience often boost long-term reliability by shortening outage duration and improving system robustness.

Electric grid resilience reflects how multiple technical, environmental and operational factors interact under stress to maintain power generation and delivery. The factors that determine a power grid’s resilience include the items listed here:

• Existing infrastructure

• Grid complexity and design

• Demand growth

• Energy transition

• Operational flexibility

• Climate change

• Cybersecurity

Energy infrastructure covers power plants, transformers, power lines and other physical equipment that generate, transmit and deliver power. Aging generation and transmission systems are more vulnerable to disruptive events.

Centralized grids with limited redundancy are easier to manage but often have critical points of vulnerability. Conversely, decentralized or distributed grids add redundancy but are more complex to design, operate and maintain.

Demand growth strains critical infrastructure and can reduce power grid resilience. For example, the rise in AI-driven data center construction has led to a corresponding increase in energy demands.

Peak demand growth poses particular resilience challenges by stressing generation and transmission capacity during extreme conditions.

The transition to renewable energy sources adds another variable to system operation and management. Intermittent power sources like solar and wind require countermeasures, such as energy storage, demand response and flexible generation to compensate for their inconsistent electricity generation.

Operational flexibility is a grid’s ability to rapidly adjust generation, load and power flows in response to changing conditions in power supply or demand. It is critical for renewable energy integration because it balances the fluctuations that can occur with intermittent power sources.

Climate change leads to increasingly unstable weather patterns, natural disasters and extreme weather events, which in turn can disrupt power supplies. Both extreme cold and extreme heat events are increasingly testing grid resilience across different regions. Record-breaking cold temperatures in January 2024 triggered the Texas power outage by stressing generation, fuel supply and grid operations.

Wildfires, floods and severe storms are all severe climate risks affecting power grid resilience. Soaring temperatures and heat waves lead to increased air-conditioner use, accelerating demand growth for electric utilities. Urban heat islands—developed areas with higher temperatures than their surroundings—further compound cooling-related issues.

The increased adoption of digital grid technologies makes power systems more vulnerable to cyberattacks. Grid operators need strong cybersecurity measures to minimize attack surfaces and maintain grid resilience against an evolving threat landscape.

2026 is a pivotal year for grid resilience due to several converging factors. Surging demand stems from increased electrification, data center construction and economic growth. Meanwhile, aging infrastructure and more frequent climate change-related natural disasters hinder the grid’s ability to meet the higher demand.

Adapting the grid with advanced technology upgrades, such as sustainability initiatives that use renewables and nuclear power is not without its own challenges. Both are capital-intensive and integrating renewable energy into legacy infrastructure is logistically complex.

Unlike intermittent renewables, nuclear plants can operate continuously and are less sensitive to short-term weather variability. However, nuclear power is subject to ongoing debate regarding safety and other concerns.

Shorter-term resiliency solutions are needed to meet the challenges of 2026 before longer-term energy sources can be brought online.

Modern grid resilience is powered by key technologies including AI, renewable energy sources and distributed networks. These approaches are the four primary methods of grid resilience improvement:

• Smart technologies

• Physical infrastructure improvements

• Distributed generation

• Energy storage

Grid operators and other stakeholders can introduce automation to energy asset management by adopting smart grid technologies. Predictive analytics models can help anticipate threats and give grid operators time to react or conduct predictive maintenance. Advanced sensors, such as phasor measurement units (PMUs), can drive automated outage detection and situational awareness.

With sufficient grid modernization, self-sensing and self-healing systems can reroute power when a disruption is detected and maintain delivery to customers. Smart technology integration can help organizations present themselves as eligible entities for infrastructure-related funding opportunities, grant programs and other partnerships.

“Hardening” the grid refers to making it more resilient to physical disruptions. Solutions include climate resilience countermeasures like taller seawalls, vegetation management, key asset relocation, fire-resistant materials and power line burial.

Rather than build new infrastructure, grid operators can use flexible alternating current transmission systems (FACTS) to balance inconsistent power delivery. FACTS help aging grids adapt to renewable energy sources without requiring new construction.

Smart technologies and physical improvements both offer energy providers an opportunity to turn climate risks into business opportunities with strategic investments.

Distributed generation (DG) is the provision of electricity through small-scale local networks as opposed to large centralized grids. Distributed energy resources (DERs) are often focused on renewable energy sources and can feature solar panels, wind turbines and energy storage systems.

DERs can power individual homes or connect to a microgrid—an independently operated grid powering a regional area, such as a university or hospital campus. Microgrids and combined heat and power (CHP) systems can connect and contribute to the wider grid while also manually or automatically quarantining or “islanding” themselves to maintain uptime during an outage.

DG systems can help mitigate power demands by supplementing grid-provided power or replacing it entirely for the areas they serve. Grid operators can then focus resources on other customers not served by a DER. Entities operating DERs can profit by selling excess power to the larger grid.

Energy storage systems are a critical component of grid modernization. Customers and utilities can maintain an electricity supply during disruptions and balance variability. Battery energy storage systems (BESS) can be deployed at the residential, commercial and utility scale, providing backup power during outages and grid services like frequency regulation, voltage support and peak shaving.

Longer-duration energy storage technologies extend these benefits by supplying power for hours or days rather than minutes. Energy storage systems enhance microgrid performance, improve system flexibility and allow grid operators to quickly restore service.

The key performance indicators (KPIs) of grid resilience allow organizations and stakeholders to assess the efficacy of their initiatives. These insights can steer further improvements and maximize efficiency.

Grid resilience KPIs include the metrics outlined here:

• SAIDI (system average interruption duration index) measures the average cumulative power outage duration per customer.

• SAIFI (system average interruption frequency index) measures the average number of outages per measurement period, often per year.

• CAIDI (customer average interruption duration index) measures the average time that it takes to restore power after an outage. SAIDI, SAIFI and CAIDI are traditionally reliability metrics but are often used as proxy indicators for grid resilience.

• Critical load performance is the maximum demand limit that a grid can withstand before suffering adverse effects, such as blackouts.

• Infrastructure hardening metrics can include miles of power lines buried, seawalls heightened, facilities upgraded and megawatts (MW) of weatherized generation.

• Microgrid number and capacity indicate how well microgrids supplement a grid in its service area.

• Threat modeling that uses predictive analytics can demonstrate the effects of extreme weather events on a grid.

• Asset vulnerability assessments identify critical infrastructure at risk of disruption.

• The customer damage function (CDF), developed by the National Renewable Energy Laboratory (NREL) through its National Library of the Rockies (NLR) program with funding from the US Department of Energy (DoE). It measures the difference in outage costs with and without resilience investments.

To date, there are no universal standards for grid resilience KPIs, though research is underway to develop a new system for measuring initiative efficacy. A 2026 paper published in Science Direct suggested a new array of DER-focused KPIs aiming to provide a more focused look at resiliency-specific developments.